1. Field of the Invention
Embodiments of the present invention relate to conveying apparatuses, systems and conveyance methodologies. More particularly, the embodiments of the invention relate to conveying apparatuses, systems and conveyance methodologies for pneumatic conveyance of solid powders such as carbonaceous fuel powders into gasifiers for gasification.
2. Description of the Related Art
Gasification is a process that enables the conversion of carbonaceous fuels, such as coal into a combustible gas, such as coal gas or synthesis gas. Generally, gasification processes include feeding carbonaceous fuels into gasifiers along with a controlled and/or limited amount of oxygen and other steams. A stable and controllable flow of such carbonaceous fuels into gasifiers is beneficial for obtaining desirable gasification performance.
Pneumatic conveyance technologies are often used to convey carbonaceous fuels into gasifiers. In conventional conveying systems employing pneumatic conveyance technologies, such conveying systems typically comprise storage tanks, feeding pipelines in fluid communication with the storage tanks, and a conveying pipeline disposed between and in fluid communication with the storage tanks and the gasifiers.
The storage tanks receive carbonaceous fuels and carrier gases through the feeding pipelines. With the introduction of the carrier gases into the storage tanks, the pressures of the storage tanks increase to desired levels, which are higher than pressures in the gasifiers so as to generate pressure differences between such storage tanks and gasifiers. A gas solid mixture then may be conveyed from the storage tanks into the gasifiers through the conveying pipeline in virtue of the pressure differences.
However, in such conventional conveying systems, the flow of the carbonaceous fuels within the conveying pipeline may have an unstable flow. For example, in a plug flow situation results in flow rates of the carbonaceous fuels within the conveying pipeline that is not uniform and thus become unstable for introduction of the carbonaceous fuels into the gasifiers. This may generate temperature fluctuations in the gasifiers, which is disadvantageous to the performance and service life of the gasifiers.
Therefore, there is a need for a new and improved conveying apparatuses, systems and methods for pneumatic conveyance of solid powders such as carbonaceous fuel powders.